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Stage 4: Black putrefaction - 10 to 20 days after death

Notes

State of decay

The bloated body eventually collapses, leaving a flattened body whose flesh has a creamy consistency. The exposed parts of the body are black in colour and there is a very strong smell of decay.

A large volume of body fluids drain from the body at this stage and seep into the surrounding soil. Other insects and mites feed on this material.

The insects consume the bulk of the flesh and the body temperature increases with their activity. Bacterial decay is still very important, and bacteria will eventually consume the body if insects are excluded.

Insect activity

By this stage, several generations of maggots are present on the body and some have become fully grown. They migrate from the body and bury themselves in the soil where they become pupae. Predatory maggots are much more abundant at this stage, and the pioneer flies cease to be attracted to the corpse. Predatory beetles lay their eggs in the corpse and their larvae then hatch out and feed on the decaying flesh. Parasitoid wasps are much more common, laying their eggs inside maggots and pupae.